Storm water runoff treatment system

ABSTRACT

A hydrodynamic device for removing sediment and other materials from storm water runoff is provided. An exemplary embodiment of this device includes: a first substantially cylindrical chamber a second substantially cylindrical chamber concentrically disposed within the upper portion of the first chamber, a first baffle concentrically disposed within the second chamber, and a second baffle disposed within the lower portion of the first chamber. A water inlet is attached to or formed integrally with the second chamber; a water outlet is attached to or formed integrally with the first chamber; and an optional bypass outlet is attached to or formed integrally with the first chamber.

RELATED APPLICATION

This is a continuation-in-part of U.S. patent application Ser. No.11/184,133, now U.S. Pat. No. 7,238,281, filed Jul. 18, 2005 for STORMWATER RUNOFF TREATMENT DEVICE, the entire disclosure of which is herebyincorporated by reference.

BACKGROUND OF THE INVENTION

This invention relates in general to water treatment devices, and inparticular to a hydrodynamic separator for removing pollutants fromstorm water runoff.

Storm water runoff from the roofs of buildings, bridges, highways,parking lots, and other urban areas often contains pollutants such asheavy metals, oil, grease, and a variety of suspended solids includingsediment, sand, gravel, and the like. When such pollutants enter areceiving body of water such as a river, stream, lake, or pond, numerousadverse environmental effects are likely. Thus, it is desirable toremove as many of these pollutants as possible before the pollutantsenter a receiving body of water.

While various systems for treating runoff are known, these devices areoften inappropriately sized, complex, expensive, difficult to configureand maintain, experience high water head loss, require power, and/or maynot adequately remove both solid and floatable pollutants prior todischarging into a receiving body of water. Thus, there is a need for aspace saving, efficient, easy to manufacture storm water treatmentdevice that may be easily installed and maintained, and that requireslittle or no electrical power for its operation.

SUMMARY OF THE INVENTION

Deficiencies in and of the prior art are overcome by the presentinvention, the exemplary embodiment of which provides a system forreducing the concentration of various pollutants found in storm waterrunoff. The system utilizes a hydrodynamic separator having at least twoconcentric cylinders.

In accordance with one aspect of the present invention, a storm waterrunoff treatment system is provided. An exemplary embodiment of thissystem includes: (a) a source of storm water runoff such as, but notlimited to, a roof, bridge, highway, street, parking lot and/or pavedsurface; (b) a hydrodynamic device for removing sediment, oil, grease,and other materials from the storm water runoff; and (c) a dischargeenvironment such as, but not limited to, a river, stream, lake, or pondfor receiving the treated storm water runoff.

In accordance with another aspect of the present invention, ahydrodynamic device or unit for removing sediment, oil, grease, andother materials from the storm water runoff is provided. An exemplaryembodiment of this device includes: (a) a first substantiallycylindrical chamber that further comprises an upper portion and a lowerportion; (b) a second substantially cylindrical chamber concentricallydisposed within the upper portion of the first chamber, wherein thefirst chamber and the second chamber form a first annular space orregion therebetween; (c) a first baffle disposed within the secondchamber, wherein the second chamber and the first baffle form a secondannular space or region therebetween, and wherein the first baffledefines an opening or passage through its length; (d) a second baffledisposed within the lower portion of the first chamber, wherein thesecond baffle further comprises a ring-shaped member and a plurality ofvertical or angled plates attached to the ring-shaped member; (e) aninlet attached to or formed integrally with the second chamber; (f) anoutlet attached to or formed integrally with the first chamber; and (g)an optional bypass outlet attached to or formed integrally with thefirst chamber.

Additional features and aspects of the present invention will becomeapparent to those of ordinary skill in the art upon reading andunderstanding the following detailed description of the exemplaryembodiments. As will be appreciated, further embodiments of theinvention are possible without departing from the scope and spirit ofthe invention. Accordingly, the drawings and associated descriptions areto be regarded as illustrative and not restrictive in nature.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated into and form a partof the specification, schematically illustrate one or more exemplaryembodiments of the invention and, together with the general descriptiongiven above and detailed description of the embodiments given below,serve to explain the principles of the invention.

FIG. 1 is a semi-transparent perspective view of the exemplaryembodiment of the hydrodynamic storm water runoff treatment device ofthe present invention showing the external and internal structure of thedevice.

FIG. 2 is a top view of the exemplary embodiment of the hydrodynamicstorm water runoff treatment device of the present invention showing thedirectional flow of water into and through the device.

FIG. 3 is a semi-transparent side view of the exemplary embodiment ofthe hydrodynamic storm water runoff treatment device of the presentinvention showing the internal structure of the device and thedirectional flow of water into and through the device.

FIGS. 4A-B are perspective and top views of a first embodiment of thesecond baffle of the present invention.

FIGS. 5A-B are perspective and top views of a second embodiment of thesecond baffle of the present invention.

FIGS. 6A-B are perspective and top views of a third embodiment of thesecond baffle of the present invention.

FIG. 7 is a top view of a fourth embodiment of the second baffle of thepresent invention.

FIG. 8 is a perspective view of a fifth embodiment of the second baffleof the present invention, wherein the plates support the second baffleabove the bottom of the outer chamber.

FIGS. 9A-B are perspective and side views of a sixth embodiment of thesecond baffle of the present invention, wherein the plates support thesecond baffle and inner chamber above the bottom of the outer chamber.

FIGS. 10A-B are perspective and side views of a seventh embodiment ofthe second baffle of the present invention, wherein the ring structureis absent and the plates support the second baffle and the inner chamberabove the bottom of the outer chamber.

FIG. 11 is a semi-transparent side view of a second exemplary embodimentof the hydrodynamic storm water runoff treatment device of the presentinvention showing the internal structure of the device and thedirectional flow of water into and through the device.

FIGS. 12A-B are perspective views of an inner cylinder, a baffle plate,and a lid for use with the device of FIG. 11, illustrated in anunassembled and assembled view, respectively.

FIG. 13 is a top view of a screen for use in the device of FIG. 11.

FIG. 14 is a top view of a screen support for use with the screen ofFIG. 13.

DETAILED DESCRIPTION OF THE INVENTION

This invention relates to systems and devices for use with storm waterrunoff. A first general embodiment of this invention provides atreatment system for storm water runoff. An exemplary embodiment ofsystem includes: (a) a source of storm water runoff such as, but notlimited to, a roof, bridge, highway, street, parking lot and/or pavedsurface; (b) a hydrodynamic device for removing sediment and othermaterials from the storm water runoff; and (c) a discharge environmentsuch as, but not limited to, a river, stream, lake, or pond forreceiving the treated storm water runoff. A second general embodiment ofthis invention provides a hydrodynamic device or unit for removingsediment, oil, grease, and other materials from the storm water runoff.An exemplary embodiment of this device includes: (a) a firstsubstantially cylindrical chamber that further comprises an upperportion and a lower portion; (b) a second substantially cylindricalchamber disposed within the upper portion of the first chamber, whereinthe first chamber and the second chamber form a first annular space orflow region therebetween; (c) a first baffle disposed within the secondchamber, wherein the second chamber and the first baffle form a secondannular space or flow region therebetween, and wherein the first baffledefines an opening or passage through its length; (d) a second baffledisposed within the lower portion of the first chamber, wherein thesecond baffle further comprises a ring-shaped member and/or a pluralityof substantially vertical or angled plates attached to the ring-shapedmember; (e) an inlet attached to or formed integrally with the secondchamber; (f) an outlet attached to or formed integrally with the firstchamber; and (g) an optional bypass outlet attached to or formedintegrally with the first chamber. The term “baffle” as it generallyrelates to the present invention is defined as “a device or structurethat deflects, checks, regulates, or reduces the flow of a liquid suchas water.” The baffles of this invention may also aid in or enhance theremoval of pollutants carried in the water.

With reference now to the Figures, the exemplary embodiment ofhydrodynamic treatment device 10 shown in FIGS. 1-3 includes asubstantially cylindrical first or outer chamber 12 that furtherincludes an upper portion 14 and a lower portion 16. A plurality ofposts 18 or another attachment member or members may be used to attachouter chamber 12 to a substantially cylindrical second or inner chamber20, which is disposed within outer chamber 12. As best shown in FIG. 2,because the outer diameter of inner chamber 20 is significantly lessthan the inner diameter of outer chamber 12, a first space or annularregion 22 is formed between the walls of two chambers. In someembodiments, a material for capturing and retaining metals is placed inannular region 22. Inlet 28 passes through the wall of outer chamber 12and is attached to or formed integrally with the outer wall of innerchamber 20. Similarly, outlet 30 is attached to or formed integrallywith the outer wall of outer chamber 12. In some embodiments, asecondary bypass outlet 32 is also attached to or formed integrally withthe outer wall of outer chamber 12 and is typically located above outlet30.

Again with reference to FIGS. 1-3, in the exemplary embodiment, a firstbaffle 34 is disposed within inner chamber 20 and is typically attachedto or formed integrally with the inner wall of inner chamber 20. Baffle34 is located near inlet 28 and typically includes a planar surface 36.As best shown in FIG. 2, because the outer diameter of baffle 34 issignificantly less than the inner diameter of inner chamber 20, a secondspace or annular region 38 is formed between the walls of the baffle andthe inner chamber. In this embodiment, baffle 34 is semi-cylindrical inshape and defines a passage 40 through its length. At least onefloatable, oil absorbing material 42 or other absorbent/adsorbentmaterial may be disposed within passage 40.

As shown in FIGS. 1 and 3, in the exemplary embodiment, a second baffle50 is disposed within the lower portion 16 of outer chamber 12 and ispartially or completely suspended above the bottom of outer chamber 12.Baffle 50 typically includes a ring-shaped support structure 52 thatfurther includes a plurality of plates 54 that are attached to andextend away from the perimeter of ring 52. Alternate configurations ofbaffle 50 are possible, and FIGS. 4A-B, 5A-B, 6, 7, 8A-B, 9A-B, and10A-B provide various views of alternate embodiments of baffle 50. Insome embodiments (see FIGS. 4A-B, 5A-B, and 6A-B), the plates 54 areconnected with, attached to, or formed integrally with the inner wall ofouter chamber 12. In other embodiments (see FIGS. 8, 9A-B, and 10A-B),baffle 50 is a freestanding structure that sits on the bottom of outerchamber 12 using plates 54 to support the baffle. In still otherembodiments (see FIGS. 9A-B and 10A-B), plates 54 are designed tosupport inner chamber 20. In the embodiment of baffle 50 shown in FIGS.10A-B, ring 52 is absent and plates 54 support inner chamber 20. Inembodiments that include a plurality of plates 54 attached to or formedintegrally with ring 52, plates 54 may be vertical or the plates may beangled upward as shown in FIGS. 6A-B. In embodiments such as those shownin FIGS. 5A-B and 6A-B, the horizontal orientation of the plates 54relative to ring 52 typically corresponds to the directional flow of thewater in outer chamber 12.

In the exemplary embodiment, the bottom portion of outer chamber 12 iseither permanently or semi-permanently closed. An upper lid 24 is usedto close the top portion of chamber 12 and a lower lid 26 is used toclose the bottom portion of chamber 12 when treatment device 10 is inuse. These lids may be completely removable or may be hinged forallowing access to the interior of treatment device 10 for cleaning orrepairs. Other types of closure devices are possible for use with thepresent invention. In some embodiments, lower lid 26 is absent and thebottom portion of chamber 12 is either completely sealed or isaccessible by way of an access pipe or aperture (not shown).

The treatment device of the present invention removes pollutants fromstorm water runoff and retains these pollutants for removal at a laterdate. With reference to the exemplary embodiment shown in FIGS. 2-3,untreated water enters device 10 through inlet 28 and flows into innerchamber 20. The inlet 28 is typically offset from the central verticalaxis of outer chamber 12. For example, the inlet 28 may be arrangedtangentially with the curved inner surface of the inner chamber 20,though that is not required. The offset inlet and the curved innersurface of inner chamber 20 encourages water entering the device to flowin a clockwise, or alternately a counter-clockwise, rotational, downwardpattern. This flow encourages solids separation and draws the settleablesolids down to the bottom of the device while simultaneously directingoil and floatables to the upper portion of the unit. After enteringinner chamber 20, untreated water enters first baffle 34 where itcontacts the absorbent/adsorbent material 42 contained within passage40. The bottom edge of first baffle 34 is typically below the standing(i.e., passive) water level within the device. Pollutants such as oilare removed from the water and held in the oil retention zone (see zone“B” in FIG. 3). The placement of first baffle 34 within inner chamber 20reduces the turbulence of the water flowing into inner chamber 20, anddirects oil and floatables to the center of passage 40, therebyenhancing the effectiveness of absorbent/adsorbent material 42.

The hydrodynamic motion (see zone “C” in FIG. 3) of the water passingthrough treatment device 10 causes the water to flow through the lengthof inner chamber 20, out of inner chamber 20, and into the lower portionof outer chamber 12 where it enters the static zone (see zone “D” inFIG. 3). The placement of second baffle 50 within the lower portion ofouter chamber 12 significantly reduces the velocity and spiraling motionof the water entering the lower portion of outer chamber 12, therebypermitting sediment, sand, gravel, dirt, and other relatively heavysuspended solids to settle out of the storm water runoff and come torest in the sediment storage zone (see zone “E” in FIG. 3). Theconstruction of second baffle 50 reduces the tendency of solids tosettle only in the center of the bottom of outer chamber 12, and reducesthe likelihood that captured solids will be “scoured” by water flowingthrough and out of device 10. In this manner, solids deposited in thebottom of outer chamber 12 are retained beneath second baffle 50 untilthe sediment is removed during periodic cleaning of the unit. Treatedwater flows upward through first annular region 22 and exits treatmentdevice 10 through outlet 30. In some embodiments, at least oneabsorbent/adsorbent material 44(see FIGS. 2 and 3) for capturing andretaining metals is disposed within annular region 22 and furtherreduces pollutant concentrations prior to the treated water exitingtreatment device 10.

Despite the inclusion of first and second baffle plates 34 and 50, highintensity flow events may be problematic for the system. To preventscouring of the retained sediment and protect the oil retention zone,bypassing of a portion of flow may be necessary under high flowconditions. If the flow of storm water runoff into treatment device 10exceeds the capacity of the device, this excess water enters the bypasszone (see zone “A” in FIG. 3) and exits device 10 through bypass outlet32.

Having generally described this invention, a further understanding canbe obtained by reference to a specific example, which is provided forpurposes of illustration only and is not intended to be all-inclusive orlimiting unless otherwise specified. A small-scale version ofhydrodynamic storm water treatment device 10 includes an outer chamber12 that is about 24 inches in height and about 12 inches in diameter,and an inner chamber 20 that is about 18 inches in height and about 8inches in diameter. Inlet 28, outlet 30, and bypass outlet 32 are allabout 3 inches in diameter and inlet 28 and outlet 30 are placed about 8inches below the top edge of outer chamber 12. The central horizontalaxis of bypass outlet 32 is about 2.5 inches above the centralhorizontal axis of inlet 28 and outlet 30. The central axis of inlet 28is offset about 3 inches from the central axis of outer chamber 12.First baffle 34 is a cut 270-300° cylinder attached to a plate, which isin turn attached to the inner wall of inner chamber 20. The dimensionsof larger versions of hydrodynamic storm water treatment device 10 willtypically be proportional to the dimensions of smaller versions,although variations are possible.

The system and device of the present invention provides numerousadvantages over existing systems and devices. For example, the compactdesign and vertical orientation of the hydrodynamic device makes thedevice useful for applications where horizontal space is limited.Additionally, the vertical configuration is immediately compatible withthe scupper drains already installed on many bridges and/or can beretrofit to treat drainage from bridges, whether or not a scupper drainis present. The position of inlet 28 may be changed to create clockwiseor counterclockwise flow as needed. The positions of both outlets 30 and32 may be changed to accommodate existing drainage systems into whichtreatment device 10 is integrated. The removable upper lid 24, whichprovides one-point access to the interior of the device, facilitatesperiodic cleaning (e.g., removal of sediment) and maintenance (e.g.,removal and replacement of absorbent/adsorbent materials). For sedimentremoval, a closeable drainage pipe may also be included in the bottom ofthe unit. In embodiments where the device is only accessible from thetop (e.g., where the unit is buried), only a single manhole is used toaccess the device. Furthermore, hydrodynamic device 10 typicallyrequires no electrical power for operation, includes an integratedbypass capability, reduces water head loss, and may be connected inparallel or in series to other treatment devices, including additionalhydrodynamic storm water runoff treatment devices.

The hydrodynamic storm water runoff treatment device of the presentinvention may be manufactured from a variety of materials using knownmanufacturing methods. Some or all of the components of the device maybe manufactured from one or more thermoplastic materials (e.g., HDPE,PVC), which are desirable in some instances (e.g., bridge applications)due to their durability and relatively light weight. For otherapplications, steel, aluminum, or even concrete may be used for some orall of the device components. Various combinations of these and othermaterials are also possible for this invention. For example, concretemay be used for the outer chamber, while one or more thermoplasticmaterials are used for the inner chamber and the other internalcomponents.

FIG. 11 illustrates a second exemplary embodiment of the hydrodynamictreatment device 100. The device 100 is substantially similar to thedevice 10 of FIGS. 1-3; thus, the description of the structure andoperation of the device 10 generally applies to the device 100. Similarto the device 10, the device 100 includes a substantially cylindricalfirst or outer container 112 that further includes an upper portion 114and a lower portion 116. The outer container 112 may be attached byplurality of posts 118 or another attachment member(s) to asubstantially cylindrical second or inner container 120, which isdisposed within outer container to form a first space or annular region122 between the walls of two containers. In some embodiments, a material144 for removing contaminants or pollutants from a fluid stream isplaced in the annular region 122. The material can be any suitablematerial for removing various contaminants or pollutants. For example,the material 144 may be designed to capture and retain metals in thefluid stream or the material may be able to remove nitrates andphosphates from the fluid stream by ion exchange or some other process.

The device 100 also includes an inlet 128 that passes through the wallof outer container 112 and is attached to or formed integrally with theouter wall of the inner container 120. Similarly, an outlet 130 isattached to or formed integrally with the outer wall of the outercontainer 112.

Furthermore, a first baffle 134, similar to the baffle 34 of the device10, is disposed within the inner container 120 to form a second space orannular region 138 between the walls of the baffle and the innerchamber. The first baffle 134 may be attached to a lid 139 that ispositioned on top of the second container 120. The lid 139 supports thefirst baffle 134 within the second container 120.

FIGS. 12A-B illustrate one exemplary method for forming the first baffle134. Other methods of forming the first baffle 134, however, arepossible. The first baffle 134 may be formed by a pipe or tube section200 and a baffle plate 202. A window 204 may be cut in the pipe section200. The window 204 may be any size desired. For example, the window 204may extend from zero to approximately two inches from the bottom of thepipe or tube section 200 to zero to approximately two inches from thetop of the pipe or tube section 200 and around approximately 90 degreesof the circumference of the pipe or tube section. Thus, an entire 90degree section of the pipe 200 may be removed or some portion of thepipe may be retained at either end of the window to provide additionalstructural support for the first baffle 134. The amount of pipe leftintact at one or more ends can be any amount that keeps the first bafflestructurally stable without significantly interfering with the flowregime of the device 100.

The baffle plate 204 may be attached to one edge of the window 204 toextend tangentially or near tangentially from the pipe of tube section.The baffle plate 204 may be attached to the pipe or tube section 200 inany suitable manner, such as, but not limited to, welding, fasteners,and adhesives. The lid 139 may be attached to the top of the tubesection. The lid 139 may be formed in a variety of ways. Any structurecapable of supporting the first baffle 134 within the second container120 may be used. In the depicted embodiment, the lid 139 is a soliddisc. The lid 139, however, could be shaped other than a disc and/orcould have one or more holes in it. The lid 139 may attach to the firstbaffle 134 in any suitable manner, such as, but not limited to, welding,fasteners, and adhesives.

Referring to FIG. 11, similar to the device 10, at least oneabsorbent/adsorbent material (not shown), such as, for example, an oilabsorbing material, or a microorganism-containing media (such as a mediacontaining bacteria that can decompose or biodegrade organic material orpetrochemicals) may be disposed within the first baffle 134.

A second baffle 150 is disposed within the lower portion 116 of theouter container 112 and is partially or completely suspended above thebottom of the outer container 112 and a screen 141 may positionedbetween the lower portion 116 and the first annular region 122. Thescreen 141 may be configured in a variety of ways. Any structure thatseparates the lower portion 116 and the first annular region 122 whileallowing fluids to flow from the lower portion to the first annularregion may be used. Referring to FIG. 13, in the depicted embodiment,the screen 141 is substantially annular having an outer diameter D1slightly smaller than the inner diameter of the first container 112 andan inner diameter D2 slightly larger than the outer diameter of thesecond container 120. In an installed position, the screen 141 may bepositioned at the bottom of the second container and substantially spansthe distance between first and second containers (see FIG. 11). Thescreen 141 may be made of any suitable material. For example, 0.2 inchmolded thermoplastic mesh has been found suitable in some applications.

Referring to FIG. 14, a screen support 143 may optionally be used toprovide structurally stability to the screen 141. The screen 141 willmount onto or be positioned on the screen support 143. The screensupport 143 is substantially annular having an outer diameter D3 aboutthe same size as the outer diameter D1 of the screen 141 and an innerdiameter D4 about the same size as the inner diameter D2 of the screen.The screen support 143 includes one or more openings 145 for allowingfluid to flow through or past the screen support.

When installed, the screen 141 or screen/screen support separates thelower portion 116 and the first annular region 122 while allowing fluidto flow past. The screen 141 also assists in retaining or maintainingwithin the annular region 122 the material 144 for removing contaminantsor pollutants from a fluid stream. For example, the material forremoving contaminants or pollutants from a fluid stream may bepositioned on top of the screen 141 such that the screen supports thematerial 144 within the annular region 122.

In the illustrated embodiment, the bottom portion of the outer container112 is either permanently or semi-permanently closed. An upper lid 124is used to close the top portion of the outer container 112 and a lowerlid 126 is used to close the bottom portion of the outer container 112when treatment device 100 is in use. These lids may be completelyremovable or may be hinged for allowing access to the interior oftreatment device 110 for cleaning or repairs. Other types of closuredevices are possible for use with the device 100. In some embodiments,the lower lid 126 is absent and the bottom portion of the container 112is either completely sealed or is accessible by way of an access pipe oraperture (not shown).

The treatment device 100 removes pollutants from a fluid stream theflows through the device and retains these pollutants for removal at alater date. With reference to the exemplary embodiment shown in FIG. 11,untreated water enters the device 100 through the inlet 128 and flowsinto the inner container 120. The inlet 128 is typically offset from thecentral vertical axis of the outer container 112. For example, the inlet128 may be arranged tangentially with the curved inner surface of theinner container 120. The offset inlet and the curved inner surface ofthe inner container 120 encourages water entering the device to flow ina clockwise, or alternately a counter-clockwise, rotational, downwardpattern. This flow encourages solids separation and draws the settleablesolids down to the bottom of the device while simultaneously directingoil and floatables to the upper portion of the unit. After entering theinner container 120, untreated water enters the first baffle 134 whereit contacts the absorbent/adsorbent material contained within the firstbaffle. The bottom edge of the first baffle 134 is typically below thestanding (i.e., passive) water level within the device. Pollutants suchas oil are removed from the water and held in the oil retention zone(see zone “B” in FIG. 3). The placement of the first baffle 134 withinthe inner container 120 reduces the turbulence of the water flowing intothe inner container 120, and directs oil and floatables to the center ofthe first baffle 134, thereby enhancing the effectiveness ofabsorbent/adsorbent material.

The hydrodynamic motion (see zone “C” in FIG. 11) of the water passingthrough the treatment device 100 causes the water to flow through thelength of the inner container 120, out of the inner container, and intothe lower portion of the outer container 112 where it enters the staticzone (see zone “D” in FIG. 11). The placement of the second baffle 150within the lower portion of the outer container 112 significantlyreduces the velocity and spiraling motion of the water entering thelower portion of the outer container 112, thereby permitting sediment,sand, gravel, dirt, and other relatively heavy suspended solids tosettle out of the storm water runoff and come to rest in the sedimentstorage zone (see zone “E” in FIG. 11). The construction of the secondbaffle 150 reduces the tendency of solids to settle only in the centerof the bottom of the outer container 112, and reduces the likelihoodthat captured solids will be “scoured” by water flowing through and outof the device 100. In this manner, solids deposited in the bottom of theouter container 112 are retained beneath the second baffle 150 until thesediment is removed during periodic cleaning of the unit. Treated waterflows upward through the screen 141 and the first annular region 122 andexits the treatment device 100 through the outlet 130. In someembodiments, at least one absorbent/adsorbent material 144 for capturingand retaining metals or removing nitrates and phosphates is disposedwithin the annular region 122 and further reduces pollutantconcentrations prior to the treated water exiting treatment device 100.

While the present invention has been illustrated by the description ofexemplary embodiments thereof, and while the embodiments have beendescribed in certain detail, it is not the intention of the Applicant torestrict or in any way limit the scope of the appended claims to suchdetail. Additional advantages and modifications will readily appear tothose skilled in the art. Therefore, the invention in its broaderaspects is not limited to any of the specific details, representativedevices and methods, and/or illustrative examples shown and described.Accordingly, departures may be made from such details without departingfrom the spirit or scope of the applicant's general inventive concept.

1. A hydrodynamic device for treating storm water runoff, comprising: afirst container; a second container disposed within the first container,wherein the first container and the second container form a generallyannular first region therebetween; a first baffle disposed within thesecond container, wherein the second container and the first baffle forma generally annular second region therebetween; an inlet attached to orformed integrally with the second container; and an outlet attached toor formed integrally with the first container.
 2. The device of claim 1further comprising a lid attached to the first baffle, wherein the lidsupports the first baffle within the second container.
 3. The device ofclaim 1 wherein the second container further comprises an inner surfaceand wherein the first baffle attaches to the inner surface to supportthe first baffle within the second container.
 4. The device of claim 1wherein the first container further comprises a lower portion andwherein a second baffle is disposed within the lower portion.
 5. Thedevice of claim 4 further comprising a screen positioned between thelower portion of the first container and the first region such thatfluid flowing between the second region and the first region passesthrough the screen.
 6. The device of claim 5 wherein the screen isgenerally annular.
 7. The device of claim 5 further comprising a screensupport positioned between the screen and the lower portion of the firstcontainer.
 8. The device of claim 1 further comprising a plurality ofattachment members that support the second container within the firstcontainer, each attachment member having a first end attached to thefirst container and a second end attached to the second container suchthat each attachment member extends across the first region.
 9. Thedevice of claim 1 wherein the first baffle defines a passage through itslength and wherein at least one absorbent or adsorbent material isdisposed within at least one of the first region and the passage.
 10. Ahydrodynamic device for treating storm water runoff, comprising: a firstgenerally cylindrical container defining a first chamber, wherein thefirst generally cylindrical container has an upper portion and a lowerportion; a second generally cylindrical container defining a secondchamber arranged about a central axis, the second generally cylindricalcontainer disposed within the first chamber and within the upper portionof the first generally cylindrical container; a first baffle disposedwithin the second chamber; a second baffle disposed within the lowerportion of the first generally cylindrical container; and a fluid inletassociated with the second generally cylindrical container such thatfluid entering the device flows in a rotational pattern about thecentral axis within the second chamber.
 11. The device of claim 10wherein the first baffle defines a passage through its length.
 12. Thedevice of claim 11 wherein a material for removing contaminants from afluid stream is disposed within the passage.
 13. The device of claim 10wherein the first generally cylindrical container and the secondgenerally cylindrical container form a first region therebetween and thesecond generally cylindrical container and the first baffle form asecond region therebetween.
 14. The device of claim 13 wherein amaterial for removing contaminants from a fluid stream is dispose withinthe first region.
 15. The device of claim 13 further comprising a screenpositioned such that fluid entering the first region passes through thescreen.
 16. The device of claim 15 further comprising a screen supportadapted to structurally support the screen in position, wherein thescreen support is a generally annular ring structure having one or moreopenings for allowing fluid to flow through the support.
 17. The deviceof claim 10 wherein the first baffle comprises a tube section having agenerally cylindrical sidewall and a plate, wherein a window if formedin the sidewall and the plate attached to an edge of the window suchthat the plate extends generally tangentially from the tube section. 18.The device of claim 17 wherein the tube section has a first end and asecond end and, wherein the window extends along the sidewall from zeroto approximately two inches from the first end of the tube section tozero to approximately two inches from the second end of the tubesection.
 19. The device of claim 17 wherein the window extends aroundapproximately 90 degrees of the circumference of the tube section. 20.The device of claim 10 wherein the first baffle defines a passagethrough its length and the first generally cylindrical container and thesecond generally cylindrical container form a first region therebetween,and wherein at least one absorbent or adsorbent material is disposedwithin at least one of the first region and the passage.
 21. The deviceof claim 20 wherein a metal absorbent or adsorbent material is disposedwithin the first region and an oil absorbent or adsorbent material isdisposed within the passage.
 22. A hydrodynamic device for treatingstorm water runoff, comprising: a first generally cylindrical containerdefining a first chamber including an upper portion and a lower portion;a second generally cylindrical container defining a second chamberarranged about a central axis, the second generally cylindricalcontainer disposed within the upper portion of the first chamber; abaffle disposed within the lower portion of the first chamber, thebaffle including a plurality of plates extending outward between thesecond generally cylindrical container and an inner wall of the firstchamber; and a fluid inlet associated with the second generallycylindrical container such that fluid entering the device flows in arotational pattern about the central axis within the second chamber. 23.The device of claim 22, wherein the plurality of plates are attached toor formed integrally with a perimeter of a ring-shaped structure. 24.The device of claim 22, further comprising an inlet attached to orformed integrally with the second container and an outlet attached to orformed integrally with the first container.
 25. The device of claim 24,wherein the inlet defines a central axis that is offset from the centralaxis of the second container.